The present invention relates to a fixing device for fixing a toner image to a sheet of paper in a copying machine.
There are known toner image fixing devices for use in copying machines, wherein two feed rollers are pressed against a heating roller for being simultaneously rotated thereby. A sheet of transfer paper carrying an unfixed toner image is fed along by being gripped between the heating roller and the feed rollers with the result that the toner image can be fixed to the sheet by being heated and dried. As the distance between the feed rollers becomes larger, the area of the sheet which is held in contact with the heating roller is greater so that the heating efficiency will be increased for drying and fixing the toner image more effectively.
If the feed rollers were spaced apart excessively, however, the sheet would tend to peel off the heating roller upwardly between the feed rollers and hence would fail to be gripped between the downstream feed roller and the heating roller, resulting in a paper jam.